Description of problem:
Clicking onto "Help" in Gimp's main menu fails.
Instead a two message boxes pop up, one telling
"Plug-in crashed: "help-browser"
(/usr/lib64/gimp/2.0/plug-ins/help-browser)
The dying plug-in may have messed up GIMP's internal state. You may want to save your images and restart GIMP to be on the safe side.
[OK]"
another one:
"Could not start the GIMP help browser plug-in.
[Cancel] [Use Web Browser]"
When lauching gimp from a terminal, at the same time an error message shows:
GLib-ERROR **: The thread system is not yet initialized.
aborting...
Version-Release number of selected component (if applicable):
# rpm -qa 'gimp*'
gimp-help-2.4.2-4.fc11.noarch
gimp-help-browser-2.6.6-3.fc11.x86_64
gimp-2.6.6-3.fc11.x86_64
gimp-libs-2.6.6-3.fc11.x86_64
How reproducible:
Always.
Steps to Reproduce:
1. on a console run "gimp"
2. In gimp's main menu click on Help->Help
3.
Actual results:
c.f. above
Expected results:
Function.
Additional info:

(In reply to comment #3)
> Hi Ralf, please test gimp-2.6.6-5 once it's available, it contains a backported
> fix needed for the new webkit version which is in F-11.
With
# rpm -qa 'gimp*'
gimp-help-2.4.2-4.fc11.noarch
gimp-help-browser-2.6.6-5.fc11.x86_64
gimp-2.6.6-5.fc11.x86_64
gimp-libs-2.6.6-5.fc11.x86_64
The Help->Help crash seems to be fixed.
However, now, the help-browser crashes on some of its submenus,
e.g. when double-clicking
"1. GIMP User Manual Authors and Contributors"
inside of the help-browser.

(In reply to comment #4)
> However, now, the help-browser crashes on some of its submenus,
> e.g. when double-clicking
> "1. GIMP User Manual Authors and Contributors"
> inside of the help-browser.
I've checked it and seen the same behaviour with webkitgtk-1.1.4 installed. Please update the webkitgtk package to version 1.1.8 which is available from updates-testing and fixed this problem for me.

(In reply to comment #7)
> Smells like an entirely broken plugin system, to me ;)
Not really, it's just the help browser plugin that's broken (with the new versions of webkitgtk which we have in F-11 and later). I've found a patch in the upstream git repo which should fix it for good, though. Expect gimp-2.6.6-6 soon in an updates-testing near you ;-).

gimp-2.6.6-6.fc11 has been pushed to the Fedora 11 testing repository. If problems still persist, please make note of it in this bug report.
If you want to test the update, you can install it with
su -c 'yum --enablerepo=updates-testing update gimp'. You can provide feedback for this update here: http://admin.fedoraproject.org/updates/F11/FEDORA-2009-7081